Affiliates were among the earliest adopters of pay per click advertising when the first pay-per-click search engines emerged during the end of the 1990s. Later in 2000 Google launched its pay per click service, Google AdWords, which is responsible for the widespread use and acceptance of pay per click as an advertising channel. An increasing number of merchants engaged in pay per click advertising, either directly or via a search marketing agency, and realized that this space was already occupied by their affiliates. Although this situation alone created advertising channel conflicts and debates between advertisers and affiliates, the largest issue concerned affiliates bidding on advertisers names, brands, and trademarks. Several advertisers began to adjust their affiliate program terms to prohibit their affiliates from bidding on those type of keywords. Some advertisers, however, did and still do embrace this behavior, going so far as to allow, or even encourage, affiliates to bid on any term, including the advertiser's trademarks.
Most businesses require startup fees as well as a cash flow to finance the products being sold. However, affiliate marketing can be done at a low cost, meaning you can get started quickly and without much hassle. There are no affiliate program fees to worry about and no need to create a product. Beginning this line of work is relatively straightforward.
Find a profitable niche. Starting with your interests, write down as many niche ideas as you can. Think about topics people might search online. Ideas include passions (like surfing or body building), fears (like spiders or speaking in front of crowds) and problems (like getting out of debt). Do keyword research to see it others are interested in the topic. Find out if a domain name is available that matches the keyword 100 percent. 
Affiliate marketing is an ideal solution for those looking to gain control of their own income by focusing on performance-based revenue options. Working in tandem with a seller, a motivated affiliate marketer will be able to achieve a passive income from the comfort of their home without worrying about producing their own product or service. Although the success of the job does depend on the affiliate’s marketing skills, it can prove to be an effective way to meet your income goals as either a primary career or a profitable second job.
Analytics are limited. Unlike with conversions made directly on your WordPress site, you’ll be limited in terms of what you can learn about the people making purchases through your affiliate links. While Amazon does provide you with details about clicks and sales, you won’t get deep insights into who the consumer was and what they did on your site before they got to that point that you would with Google Analytics.